Effect of Water Vapor on Electrical Properties of Individual Reduced Graphene Oxide Sheets

Abstract

The electrical conductivity and gas-sensing characteristics of individual sheets of partially reduced graphene oxide are studied, and the results display a strong dependence on the chosen reduction method. Three reduction procedures are considered here: thermal, chemical, and a combined chemical/thermal approach. Samples treated by chemical/thermal reduction display the highest conductivity whereas thermally reduced samples display the fastest gas-sensing response times. The chemo-resistive response to water vapor adsorption is well fit by a linear driving force model. The conductivity upon exposure to water vapor and measured as a function of the gated electric field displays significant hysteresis. These results illustrate how the chemical structure of graphene oxide may be tailored to optimize specific properties for applications such as field effect devices and gas sensors.

Electrospray-printed nanostructured graphene oxide gas sensors

“…The power consumption of the printed sensors was estimated at 6 μW or less over the 10-60% RH range. The increase in resistance of the GO sensors with increasing RH found in these experiments followed the same behavior observed for reported sensors made with drop-cast graphene thin films [15], electrosprayed rGO thin films [26], individual rGO sheets [31], rGO/polymer nanocomposites [32], and randomly oriented carbon nanofibers [33].…”

Chemical functionalization of graphene oxide for improving mechanical and thermal properties of polyurethane composites

“…Before using, GO was vacuum freeze-dried to reduce the amount of stored water in its π-stacked structure [26]. In a typical operation, 300 mg GO was added into a round-bottom flask followed by 150 ml anhydrous DMF under a nitrogen atmosphere to form a homogeneous suspension with the aid of an ultrasonication bath.…”

NO2and humidity sensing characteristics of few-layer graphenes

“…Functionalised graphite nanostructures are able to sense traces of pollutant gases such as NO 2 [30]. Water vapour sensing characteristics of reduced graphene oxides have been reported [31]. Reduced graphene oxide is also shown to be a good sensor for toxic vapours [32].…”